William henry elkins



m A NL TLC KR LA X .E Hm n L W M m M M No 445,136. Patented Jan. 20, 1891.

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UNITED STATES PATENT OFFICE.

\VILLIAH HENRY ELKINS, OF CAMBRIDGE, MASSACHUSETTS, ASSIGNOR OF TlVO-TIIIRDS TO HENRY E. IRYINF, OF NE\Y YORK, N. Y.

MULTIPLEX-ARC LAMP.

SPECIFICATION forming part of Letters Patent No. 445,136, dated January 20, 1891.

Ap )1icati0n filed October 25, 1890. Serial No. 369,271, (No model.)

To all whom it may concern.-

Be it known that I, WILLIAM HENRY En KINs,of Cambridge, in the county of Middlesex and State of Massachusetts, have invented a new and useful Improvement in Electric Lamps, of which the following is aspecification, reference being had to the accompanying drawing, making a part hereof, and which is an elevation, partly in section,illus trating two are lamps connected by a shunt circuit and an automatic switch, all embodying my invention in the best form now known to me.

In a previous application for United States Letters Patent. Serial -N0. 360,096, filed July 26, 1S90,I have described all that is shown in the drawing, except only the electrodes ff and the peculiar shunt-circuit of which they form a part; and mypresent invention is the combination of two lamps with a switch whose movable portion is controlled bya shunt-magnet whose circuitremains open until the electrodes ff, controlled by the carbon-carrier ot the first lamp, come into contact, thereby closing the shunt-circuit, which energizes its i magnet and shifts the switch.

In the drawing there are two lamps A A, one in circuit, the other out of circuit. The lamp A operates precisely as usual until its carboirliolder comes down far enough to bring electrode f into contact with electrode f,when the shunteircuit through magnet I is closed. Then as the carbons of lamp A are burned out the resistance between them is increased suliiciently to cause a current through magnet B strong enough to attract its armature and shift switch D, thereby bringing contact (1 into contact with block d,electrically connected with lamp A and separating contact (Z from block {1", thus automatically cutting out lamp A and cutting in lamp A.

The construction and operation of the parts marked A, A, B, b, I), D, (Z, d, (Z (Z and d are fully described in my pending application, and these parts are individually too well known to require further description.

The main feature of my former invention is to connect two are lamps by an automatic switch controlled by a circuit through magnet Il,which broke that circuit. when the switch operated, and while this invention is highly desirable in connection with my present invention it will be obvious that my present invention consists in keeping the circuit through magnet 13 open until it is closed by the descent of the movable carbon-carrier, and that it may be used either with or without my former invention above referred to; but both inventions are here shown, because an apparatus for connecting two independent lamps which embodies both is in myjudgment the best form of appa atus for embodying either.

\Vhat I claim as my invention is* 1. In combination, a switch with two blocks, a shunt-magi] et controlling the movable member of the switch, two lamps, conductors connecting the like poles of the lamps to one of the main terminals, other conductors connecting the other poles of the lamps to the blocks of the switch, and a shunt-circuit, of which the coil of the controlling-magnet forms a part, and which contains two electrodesff', controlled by the carboircarrier of one of the lamps, all substantially as set forth.

2. In combination, a spring-switch with two blocks, a shunt-magnet controlling the movable member of the switch, two lamps,conductors connecting the likepoles of thelamps to one of the main terminals, other conductors c011- necting the other poles of the lamps to the blocks of the spring-switch,and a sh u nt-circuit of which the coil of the sWitclrcOntrOlling magnet forms a part, and which is adapted to be made and broken at two places, one by the contacts ff, controlled by the carbon-carrier, and the other by the contacts (I (1", controlled by the switch, all substantially as set forth.

XVILLIAM HENRY ELKINS.

\Vitnesses:

EDWARD S. BEACH, JOHN R. Snow. 

